I find that often if I get the tournament lead early on, then I will go on to win the tournament, or finish high.
The question is how do you get that big stack if you are not getting good cards and not getting into big pots?
My first tactic is often to bluff as necessary in small pots enough to stay around the starting number of chips. The next tactic is to get them all in preflop, in which case you will either double up or lost, but this tends to result in just winning small pots preflop, especially early in a tournament when the blinds are low.
However, if UTG shoves and gets two callers, then even with a fairly mediocre hand like 86o in the blinds, then you are actually second favorite to win if the other hands are AA, QQ, and JJ.
If you do win, then you will take your stack from 5000 to 20000, or something like that and vastly increase your chance of winning the tournament. Now you can threaten smaller stacks with elimination at any time, and they will be cautious about bluffing you and you can afford to make your bluffs a bit bigger than usual to determine whether they really have hands that they are willing to go all the way with. When you float the flop then raise on the turn with nothing, that pts them in a tough spot as you can be representing trips or two pairs.
I think you should only consider this move with hands that are not dominated hands like suited aces and any hands containing a K, Q, or J, and suited hands are preferable as a flush is often the hand that takes down a pair of Aces.
In this kind of situation, you also have the distinct and delicious possibility that all three of the other hands are blocking each other, perhaps AK vs AK, or all three hands have aces.
With a medium pocket pair, I would be more inclined to fold.
Another tactic for an early double up is, when you flop top pair, is to check to opponent, then call their bet/bluff, then shoving the turn with top and letting opponents draw for a straight or flush with the odds against them if it looks like they are on a draw. This is risky as opponent may have top pair with a better kicker, or may have something better than top pair, but then again, an early double up puts you in the driver seat.
Once you have that megastack, you can play very tight for a long while and only play premium hands and pocket pairs preflop, looking to stack opponents with deceptive play.